add loft_demo

src/experimental/demo/loft_demo.scad

@@ -0,0 +1,12 @@
+use <shape_starburst.scad>;
+use <rotate_p.scad>;
+use <experimental/loft.scad>;
+    
+sects = [
+    for(i = [4:20])
+    [
+        for(p = shape_starburst(15, 12, i % 2 == 1 ? i : i - 1))    rotate_p([p[0], p[1], 3 * (i - 4)], i * 10)
+    ]
+];
+
+loft(sects);